To Remove Auto-Thread Cutter (New Type) - Singer s18 Service Manual

The thread cutter mechanism was modified to improve the performance.
If the thread cutter does not function well, replace the thread cutter unit. When replacing old type of the thread cutter with
new one, replace also the arm (1) with new type.
Note: The part number of the arm (1) has been changed from 846153007 to 846233000.
Thread cutter unit (Old type)
Link unit
Arm
Spring
Snap ring
E-4 (C)
Thread cutter unit (New type)
Replacement of the Thread Cutter Unit (new type)
Setscrews (A)
Snap ring E-3 (B)
Arm
Link Snap ring E-3 (B)
1. Remove the needle plate. Remove the two set
screws (A) and the thread cutter unit.
2. Remove the snap ring E-3 (B) to release the link.
3. Remove the snap ring E-4 (C) and slide the link to
disengage it from the actuator arm (1).
Rotate the arm to the position shown in the dotted
line and remove it.
4. Place the revised arm (1) on the pin, along with the
spring. Insert the snap ring E-4 (C) between the arm
(1) and the bottom end of the spring.
5. Slide the link back to engage it with the arm (1).
Insert the snap ring E-3 (B).
6. Place the revised thread cutter unit and secure it
with the setscrews (A). Attach the needle plate.
Note:
After replacement, check the position of the thread
cutter switch and thread cutter sliding plate. (Refer to
page s 37 and 26.)
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